129660228 has 72 divisors (see below), whose sum is σ = 340494336. Its totient is φ = 41558400.

The previous prime is 129660217. The next prime is 129660233. The reversal of 129660228 is 822066921.

It is a happy number.

129660228 is a `hidden beast` number, since 1 + 29 + 6 + 602 + 28 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 129660192 and 129660201.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 248608 + ... + 249128.

It is an arithmetic number, because the mean of its divisors is an integer number (4729088).

Almost surely, 2^129660228 is an apocalyptic number.

129660228 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129660228, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (170247168).

129660228 is an abundant number, since it is smaller than the sum of its proper divisors (210834108).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

129660228 is a wasteful number, since it uses less digits than its factorization.

129660228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 785 (or 780 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 129660228 is about 11386.8445146142. The cubic root of 129660228 is about 506.1379794211.

The spelling of 129660228 in words is "one hundred twenty-nine million, six hundred sixty thousand, two hundred twenty-eight".